1 - Describing demographic change

Summary

Population growth in a city is not uniformly distributed over time, or within its urban structure. From an interurban perspective, the differential urbanization model, proposed by Hermanus Geyer and Thomas Kontuly in the 1990s, posits that the growth of cities in a country changes over time according to the size of urban agglomerations (Geyer & Kontuly 1993). During the first stage, the largest city is the one with the greatest population dynamism, because it is the point of arrival of internal migration from rural localities. A group of medium-sized cities subsequently vie with the primary city as internal migration destinations, encouraging the phase of polarization reversal. The authors propose a third stage, counter-urbanization, characterized by the fact that small cities are those with the highest population growth rates, due to migratory movements of rural and urban origin with these population centres as their destination. In this model, internal migration movements mainly explain the demographic dynamics of the city.

Intraurban demographic change has been studied through the metropolitan geography patterns of population and employment, generally characterized by an initial displacement of the population and subsequently of employment, from the central city to the periphery, giving rise to suburbanization processes (Gottdiener et al. 2016: 138– 41; Piña 2014), as well as the emergence of polycentric urban structures (Champion 2001; Rodríguez 2012). The stages of metropolitanism correspond to (1) urbanization or concentration, when the greatest demographic growth takes place in the central city; (2) suburbanization, when the periphery achieves the highest rate of population growth; (3) de-urbanization, when the central city loses population in absolute terms; and (4) repopulation, when the central city resumes the path of demographic growth (van den Berg et al. 1982; Suarez-Villa 1988). The suburban and peripheral areas of the city are mosaics of diversity in the socioeconomic conditions of the resident population, as well as opportunities for the location of economic activities.

Based on these precepts, this chapter studies the demographic dynamics of the Mexico City Metropolitan Area (ZMCM) in the period 1980– 2020, the patterns of territorial distribution of the population on the interurban or regional, and intraurban, or metropolitan scale, and the main sociodemographic features of the resident population.